Only 23 per cent of the total vehicles registered under the Public Vehicles Department (PVD) of the state transport department had undergone pollution under control (PUC) test every year from 2010 to 2016 and the remaining 77 per cent vehicles had been plying without the PUC. The latest audit report of the Comptroller and Auditor General (CAG) of India made this startling revelation, throwing light on how auto emission is polluting the air in the city and adjoining towns.

The CAG observed after verifying the PUC certificates of all five state transport undertakings (STUs) ~ Calcutta State Transport Corporation (CSTC), Calcutta Tramways Company (CTC), West Bengal Surface Transport Corporation (WBSTC), South Bengal State transport Corporation (SBSTC) and North Bengal State Transport Corporation (NBSTC), ~ that only one parameter such as smoke density test was conducted as per the CPCB rules.

But the showcause notices issued by the transport department to 78 state buses operated by the then three corporations claimed that all the four parameters were checked in these fleets. CSTC had conducted only smoke density tests in-house while the four other corporations had outsourced the checking system to automobile emission checking centres, the CAG mentioned in its report.

In 2016, the government set up the West Bengal Transport Corporation (WBTC) merging three undertakings ~ CATC, CTC and WBSTC ~ bringing them together under one umbrella. In December, 2017, the state environment department in its reply had informed that PUC standard for onroad diesel-driven vehicles was considered only on the basis of smoke density tests. But the reply was not acceptable because as per the West Bengal Pollution Control Board (WBPCB) norms, pollution level of vehicles was considered after verifying all the four criteria.

The audit revealed that check of records relating to testing pollutions (smoke density) caused by buses was done at 16 out of 55 depots of the five STUs in 2016-2017. It was found that the 16 depots had conducted smoke density tests on 952 occasions in the same period but the requirement of conducting such tests were 2,251. It showed that only 42.29 per cent of statutory PUC tests were done.

The state transport department did not obtain any PUC certificate for 85 government buses at the Howrah depot close to the Howrah district administrative head quarters. Twenty-four of these buses were more than 10 years old.

Similarly, the depots at Belghoria, Arambag and Durgapur under the SBSTC had never conducted smoke tests for 149 buses and this showed that the compliance of auto emission standards in these 234 state buses was never ascertained, the CAG report revealed. Depots under the CSTC did not also calibrate its smoke testing machines during 2017. As a result, the readings figured by the CSTC’s smoke testing equipment were not reliable, according to the findings of the CAG.